Sima Yong

Sima Yong (died 306) was Prince of Hejian from 277 to 306 and the seventh of eight Jin princes associated with the War of the Eight Princes of 291-306 AD.

Biography
Sima Yong was the grandson of Sima Fu, the younger brother of Sima Yi, and he was created Prince of Hejian by Emperor Sima Yan in 277. In 299, under Emperor Sima Zhong, he was made commander of Chang'an. In 301, when Sima Lun usurped the throne from Sima Zhong, Sima Yong and his general Zhang Fang initially supported Sima Lun before joining Sima Jiong and Sima Ying's rebellion. The rebellion was successful, but Sima Jiong was hostile towards Sima Yong for his former loyalty to Sima Lun. Sima Yong invited Sima Ai and Sima Ying to rebel against Sima Ai, and, in the winter of 302 AD, Sima Jiong attempted to launch a pre-emptive strike against Sima Ai, only to die in battle. Sima Ai then became regent, and he submitted all important matters to Sima Ying, passing over Sima Yong. In 303, Sima Yong and Sima Ying rebelled against Sima Ai, and, in 304, Sima Yue and the officials in Luoyang joined the rebellion and ultimately captured and executed Sima Ai. Sima Ying and Sima Yue then went to war, and, despite Ying's victory at the Battle of Dangyin, the Xiongnu invasion ultimately led to Sima Ying's army deserting him. When Sima Ying arrived in Luoyang with the Emperor, Sima Yong betrayed him and deposed him as crown prince, replacing him with Sima Chi. Sima Yong became the seventh prince to serve as regent for the Emperor, but, in 305 AD, Sima Yue rebelled against Sima Yong after he improperly forced the Emperor to move the capital. In 306 AD, Sima Yong executed Zhang Fang in a gesture of peace, but Sima Yue refused, and Sima Yong was forced to abandon both Luoyang and Chang'an that same year. Sima Yong soon recaptured Chang'an, and Sima Yue decided to make peace by offering Sima Yong a high-ranking position. However, on his way to Luoyang, Sima Yong and his three sons were ambushed and killed by Sima Yue's brother Sima Mo, ending the war.